New Insights into Ligand-Receptor Pairing and Coevolution of Relaxin Family Peptides and Their Receptors in Teleosts

Figure 9

Proposed Rln/Insl-Rxfp ligand-receptor pairings based on previous genomic data (see Figure 4) and the analyses presented here. Solid lines represent potential ligand-receptor relationships that are well supported, while dashed lines represent uncertain pairings. There are four receptor orthologs between mammals and teleosts, and the data support the same ligand-receptor pairings for these genes in teleosts. For the seven teleost-specific receptors, strong ligand-receptor pairings were supported for three (solid lines), while the other three Rxfp3-3 receptors have unclear pairings (dotted lines), and Rxfp2-like is a probable secondary receptor for Rln.